I always assumed the botted accounts on Reddit were in the hands of marketing companies, ready to upvote posts saying "My Brand X headphones sound great" or "I changed from Brand Y to Brand Z cigarettes because the smooth taste never leaves me feeling over-smoked" or "I made big gains by putting my life savings into this sketchy investment" or whatever they're being paid to promote at the time.

I'd wager you could do a lot to influence public opinion with just an upvote ring, without the botted accounts actually needing to post messages.